[Q3] The following test results are obtained from a three-phase 60 hp, 2200 V, six-pole, 60 Hz squirrel-cage induction motor. (1) No-load test: Supply frequency = 60 Hz, Line voltage = 2200 V Line current = 4.5 A, Input power = 1600 W (2) Blocked-rotor test: Frequency = 15 Hz, Line voltage = 270 V Line current=25 A, Input power = 9000 W (3) Average DC resistance per stator phase: R1 =2.8 2. Determine the no-load rotational loss, stator current, P.F and efficiency.

[Q3] The following test results are obtained from a three-phase 60 hp, 2200 V, six-pole, 60 Hz squirrel-cage induction motor. (1) No-load test: Supply frequency = 60 Hz, Line voltage = 2200 V Line current = 4.5 A, Input power = 1600 W (2) Blocked-rotor test: Frequency = 15 Hz, Line voltage = 270 V Line current=25 A, Input power = 9000 W (3) Average DC resistance per stator phase: R1 =2.8 2. Determine the no-load rotational loss, stator current, P.F and efficiency.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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